From Microsoft adCenter labs is a potentially quite powerful tool that predicts the demographics for a particular search term.

"You can use adCenter technology to predict a customer's age, gender, and other demographic information according to his or her online behavior-that is, from search queries and webpage views. General Distribution is the breakdown by age of MSN Search users-based on a one-month MSN Search log-regardless of search query used. Predicted Distribution is the predicted breakdown by age of MSN Search users for a single search query, based on the adLabs predictive model."

Microsoft, adCenter, demographics, statistics